Message-ID: <4D028B91.5050408@ccbr.umn.edu>
Date: 2010-12-10T20:20:33Z
From: Erik Iverson
Subject: Reorder factor and address embedded escapes
In-Reply-To: <4D028A0C.3010801@aetiologic.ca>
Does the following help?
A = c("A\\nB", "C\\nD")
test <-data.frame(A)
#access levels directly to change names
levels(test$A) <- sub("\\\\n", "\n", levels(test$A))
#re-order levels of the factor
test$A <- relevel(test$A, "C\nD")
Rob James wrote:
> I am trying to reorder a factor variable that has embedded escape
> characters. The data begins as a csv file with a factor that includes
> embedded new line characters. By the time read.table has rendered it
> into a data frame, the variable now has an extra backslash.
>
> e.g.
> "This\nLabel" in the csv becomes "This\\nLabel" in the data frame.
>
> So, I am trying to reorder the factor and deal with the introduction of
> a secondary \ . Here's a small example:
>
>
> A = c("A\\nB", "C\\nD")
> test <-data.frame(A)
> str(test)
> test$reorderA <-factor(test$A, c("C\\nD", "A\\nB"))
> str(test)
> test$reorderB <-sub("\\\\n", "\n", test$reorderA)
> str(test)
>
> When sub is applied to the now-correctly ordered factor, it returns to
> the default ordering.
>
> Suggestions?
>
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